login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A214132 Lesser term of smallest primitive friendly pair such that both terms are divisible by the n-th prime p and coprime to the primes below p. 2
6, 135, 14105, 15506071, 432712085377, 1890948943, 14783271043, 45847, 211838579, 147560225903398137982300169126840969637180767467, 12060713581457342807125295910808091355523729 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
For n>2, instances are known up to 11 (p=31).
By definition, gcd(a(n), A002110(n-1)) = 1. - Michel Marcus, Jan 19 2014
LINKS
Achim Flammenkamp, The Multiply Perfect Numbers Page (for p = 13, 17, 19)
EXAMPLE
For n=1, the perfect numbers 6=2*3 and 28=2^2*7 (A214133) are primitive friendly.
For n=2, 135=3^3*5 and 819=3^2*7*13 (A214133) are primitive friendly.
CROSSREFS
Cf. A214133. Subset of sequence A096366.
Sequence in context: A333005 A013299 A013295 * A196703 A196852 A196946
KEYWORD
hard,more,nonn
AUTHOR
Michel Marcus, Jul 05 2012
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 17 23:23 EDT 2024. Contains 371767 sequences. (Running on oeis4.)